How to Control Pond Algae

Pond algae aren’t problematic so long as the natural elements that enable algal growth are controlled. It is important to keep your pond clear from floating debris and to use a good filtration system. When algae appear, it’s just a sign that there are other problems and that your pond is out of balance.

There are many easy, short-term chemical fixes available to kill algae quickly but the problem lies in that the fix is short-term. Rather than taking other measures to prevent algae, some pond owners just overuse the chemical, leaving the plants, fish and other living organisms susceptible to poisoning. Also, killing the algae and leaving it in the water to degrade causes another algae problem in that it requires more oxygen to break down the waste. In scenarios where ponds have extreme algae problems, it is recommended to kill of the algae in stages so that there is not too much decaying vegetation the pond has to contend with.

While the long-term approach doesn’t work as quickly as the short-term approach, it does involve utilizing methods that control the sources of algae – nutrients, sunlight and low dissolved oxygen.  This type of control does not work as quickly, but it is safer, more cost effective and is efficient because it creates a more harmonious natural balance in your pond with maintenance. After all, you only get out of it what you put into it!

Nutrient Control

Keep your pond clear of floating debris. Manually remove dead leaves, grass clippings and vegetation from the water with a skimmer, rake or net. Filtration is very important as well. Selecting a filter that offers both mechanical and biological filtration will help immensely with small debris such as fish waste and uneaten fish food. Effective nutrient control for small fish ponds begins with not overpopulating the pond. Many people subscribe to the rule of 1” of fish per 10 gallons.

Controlling run-off is another way to help against nutrient overload. Construct a fence or barrier around the perimeter of the pond. Better yet, plant surrounding grass around the pond and use non-chemical treatments. This introduces less fertilizer to your pond and helps keep some of the run-off from other pastures out of the pond water.

Sunlight Reduction

The sun adds another critical element for algae growth. While there are fewer options for controlling the amount of sun your pond is exposed to on a daily basis, the options are pretty effective.

The most common option is to add a dye or colorant to the water. The colorant tints the water, limiting the penetrative effects of sunlight and limiting the algae’s ability to photosynthesize.

The addition of aquatic plants can help shade the pond surface. Lilies or lotus can be planted to provide shade for the water and add a beautiful, natural touch to the pond. Other floating aquatic plants offer both shade and the ability to absorb nutrients from the water. Be sure to keep the pond clear of floating leaves and other debris from aquatic plants and grasses.

Oxygenation 

Algae hates well oxygenated, circulating water and a proper pond aerator can provide both.  Thorough oxygenation will help break down organic waste more speedily by invigorating beneficial pond bacteria that plays a role in breaking down organic waste. Aeration also makes the use of algaecides safer as it protects against fish kills if too much algae dies off too fast.

Taking the long-term route to clearing a pond of algae ensures that the pond will be clearer longer and it creates a harmonious balance to the life in and around your pond. Keep algae away naturally. It’s cheaper than the quick-fixes and it is more efficient, allowing maximum enjoyment of your pond.